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ELE3BF
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1992-01-26
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FCC GENERAL Exam Question Pool. Subelement 3BF.
Circuit Components. ? Questions.
---------------------------------------------------
3BF 1.5 C
What is the effect of an increase in ambient temperature on
the resistance of a carbon resistor?
A. The resistance will increase by 20% for every 10 degrees
centigrade that the temperature increases
B. The resistance stays the same
C. The resistance change depends on the resistor's temperature
coefficient rating
D. The resistance becomes time dependent
3BF 2.6 D
What type of capacitor is often used in power supply circuits
to filter the rectified AC?
A. Disc ceramic
B. Vacuum variable
C. Mica
D. Electrolytic
3BF 2.7 D
What type of capacitor is used in power supply circuits to filter
transient voltage spikes across the transformer secondary winding?
A. High-value
B. Trimmer
C. Vacuum variable
D. Suppressor
3BF 3.5 C
How do inductors become self-resonant?
A. Through distributed electromagnetism
B. Through eddy currents
C. Through distributed capacitance
D. Through parasitic hysteresis
3BF 4.1 A
What circuit component can change 120-VAC to 400-VAC?
A. A transformer
B. A capacitor
C. A diode
D. An SCR
3BF 4.2 B
What is the source of energy connected to in a transformer?
A. To the secondary winding
B. To the primary winding
C. To the core
D. To the plates
3BF 4.3 A
When there is no load attached to the secondary winding of a
transformer, what is current in the primary winding called?
A. Magnetizing current
B. Direct current
C. Excitation current
D. Stabilizing current
3BF 4.4 D
In what terms are the primary and secondary windings ratings
of a power transformer usually specified?
A. Joules per second
B. Peak inverse voltage
C. Coulombs per second
D. Volts or volt-amperes
3BF 5.1 C
What is the peak-inverse-voltage rating of a power supply
rectifier?
A. The highest transient voltage the diode will handle
B. 1.4 times the AC frequency
C. The maximum voltage to be applied in the non-conducting
direction
D. 2.8 times the AC frequency
3BF 5.2 B
Why must silicon rectifier diodes be thermally protected?
A. Because of their proximity to the power transformer
B. Because they will be destroyed if they become too hot
C. Because of their susceptibility to transient voltages
D. Because of their use in high-voltage applications
3BF 5.4 D
What are the two major ratings for silicon diode rectifiers
of the type used in power supply circuits which must not be
exceeded?
A. Peak load impedance; peak voltage
B. Average power; average voltage
C. Capacitive reactance; avalanche voltage
D. Peak inverse voltage; average forward current
--------------------------------------------------
End of Subelement 3BF.